Europe's Largest Battery Storage System Goes Online

One of the biggest drawbacks of renewable energy, so far at least, is that power generation can be intermittent. While fossil fuel and nuclear plants are very predictable in the amount of power that they output, a cloudy day or a drop in wind speed and the amount of renewable energy that can be generated drops dramatically. Too much wind can even be a problem at times for wind power. This may change in the future when more reliable and predictable renewable resources, such as tidal power, come online, but until then it is something we have to deal with. The best way to overcome this problem is to store energy during high generation periods and use the stored energy to supplement the grid in times when less power is generated. Other generation methods can be used to cover for dips in renewables when the energy generated drops over a longer period of time.

Scientists are currently working on a few different methods of storing the excess energy generated. These include storing the energy as heat in molten salt batteries, or using hydroelectric batteries where water is pumped uphill when there is excess energy and run through generators at times of need. In time, these techniques may become the preferred method of large-scale energy storage, but at the moment the drawbacks outweigh their usefulness. Until these problems are overcome, we have to use the technology we already have, and in the case of large-scale storage, that is normal electrochemical batteries.

The largest of this type of battery in Europe (by Mwh) has just entered operation. Harmony Energy Income Trust has energised the company’s 98 MW / 196 MWh (megawatt hours) Pillswood project last week. The project comprises of Tesla 2-hour Megapack technology systems and can store up to 196 MWh of electricity in a single cycle - enough energy to power around 300,000 UK homes for two hours. The project was designed to provide critical balancing services to the UK’s electricity grid network, allowing the replacement of coal and gas power stations with renewable power sources. This project and others will allow the National Grid to maximise the efficiency of wind farms by reducing the amount of time a wind farm needs to be curtailed due to supply/demand imbalances or network constraints.

The Pillswood project is situated close to Hull in the east of the UK. It is next to the National Grid's Creyke Beck substation, which will be the connection point for Phase "A" and "B" of Dogger Bank, the world's largest offshore wind farm. The first phase of the wind farm is expected to go live in the summer of 2023.

The project was developed by Harmony Energy Limited and its construction was managed by Tesla. The original plan called for the project to become operational over two phases in December 2022 and March 2023, but the timetable was accelerated to enable both phases to complete in November 2022.

Tesla's Autobidder algorithmic trading platform will operate the project. The platform has previously been used to operate the Holes Bay and Contego projects (two earlier battery storage projects developed by Harmony Energy Limited along with FRV)). The two projects are the top performing battery projects by revenue generation in the UK over the last year.